Portable vaporizer and method for temperature control

ABSTRACT

A vaporizer and method of vaporizing a botanical material is described. Embodiments of the apparatus include a self-contained, fully enclosed, battery operated vaporizer having an air inlet and a mouthpiece. The vaporizer includes a window for viewing a botanical material contained therein and a heating element that is also visible through the window and through an air inlet. The vaporizer also includes a push-button switch that rapidly provides power to heat air, which is then drawn through the botanical material by inhaling. Embodiments of the method include utilizing a push-button switch for heating vaporizer air and viewing the glow of the heating element as a signal that the vaporizer is ready for use. In certain embodiments, electric power for heating the air is varied according to the temperature of the vaporizer. Certain other embodiments measure the battery voltage and adjust a heater duty cycle according to the measured voltage.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/902,038, filed Nov. 8, 2013, the contents of which are herebyincorporated by reference in its entirety

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to the field of vaporizers forconsuming botanical materials, and more particularly to an apparatus andmethod for operating a vaporizer for heating the materials.

2. Discussion of the Background

Devices for consuming botanical materials, including but not limited totobacco, flowers, botanical blend, or aromatic herbs, commonly ignitethe botanical materials, requiring that the consumer inhale products ofcombustion along with any volatile compounds that are present. For manybotanical materials it is the volatiles, such as the nicotine present intobacco, that provide a physiological response in the consumer, whilethe combustion products may actually be harmful.

Prior art vaporizers commonly employ a continuous heating source such asa butane-powered flame, a butane powered catalytic burner, or anelectrical resistive heater. The heat source in many such devices isconductive as it is in direct contact with the material or thereceptacle containing the material. This may result in hightemperatures, leading to singing and charring of the botanical materialnear the heat source.

Further, many prior art vaporizers require several minutes of heat-uptime as they need to heat both the mass of the botanical material and aholder of the material to a desired temperature before they can extractvolatile vapors.

Further, since the heating is typically continuous, rather thanon-demand, many existing vaporizers use their power inefficiently asthey are often providing heat to maintain a steady state of elevatedtemperature that does not correspond to the user's intended duty-cycleof intermittent inhalation of the vapors produced.

BRIEF SUMMARY OF THE INVENTION

One embodiment of the present invention overcomes the disadvantages ofprior art by controlling the power provided to vaporize a botanicalmaterial according to the temperature of the vaporizer.

It is one aspect of the present invention to provide a method ofcontrolling electric power provided to a vaporizer, where the methodincludes: accepting a signal from a user-operable switch; providingelectric power to a heater of the vaporizer upon accepting the signalfrom the user-operable switch; measuring a signal indicative of thetemperature of the vaporizer; and decreasing the electric power to theheater if the measured temperature of the vaporizer increases.

It is another aspect of the present invention to provide a vaporizerincluding: a user-operable switch; a temperature sensor adapted toprovide a signal indicative of the temperature of the vaporizer; anelectric heater configured to heat the botanical material; andelectronics adapted to sense actuation of the user-operable switch andaccept the signal, and to provide electric power to the electric heater,where the provided electric power decreases with an increase in thetemperature of the vaporizer.

It is one aspect of the present invention to provide a method ofcontrolling electric power provided to a vaporizer. The method includesmeasuring the voltage of a battery providing power to the heater, andproviding the battery voltage to a heater of the vaporizer according toa duty cycle, where the duty cycle is inversely proportional to themeasured voltage of the battery.

It is another aspect of the present invention to provide a vaporizer toprovide a user with vapor from a botanical material. The vaporizerincludes a battery having a voltage; an electric heater that accepts thevoltage and generates thermal energy to heat the botanical material; andelectronics to switch the accepted voltage on and off according to aduty cycle, where the duty cycle is inversely proportional to a measuredvoltage of the battery.

These features together with the various ancillary provisions andfeatures which will become apparent to those skilled in the art from thefollowing detailed description, are attained by the vaporizer of thepresent invention, preferred embodiments thereof being shown withreference to the accompanying drawings, by way of example only, wherein:

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a top perspective view of one embodiment of a vaporizer;

FIG. 2 is a top view of the vaporizer of FIG. 1;

FIG. 3 is a left side view of the vaporizer of FIG. 1;

FIG. 4 is a distal end view of the vaporizer of FIG. 1;

FIG. 5 is a proximal end view of the vaporizer of FIG. 1;

FIG. 6 is a top perspective view of the vaporizer of FIG. 1 with theupper portion removed from the lower portion;

FIG. 7 is a sectional view 7-7 of FIG. 2;

FIG. 8 is a sectional view 8-8 of FIG. 3;

FIG. 9 is an exploded view of one embodiment of a heater block;

FIG. 10 is a perspective view of a partially assembled heater block;

FIG. 11 is the view of FIG. 6 illustrating air flow through thevaporizer;

FIG. 12 is a cut-away perspective sectional view of the embodiment ofFIG. 11; and

FIG. 13 is a schematic view of one embodiment of the electronics withinthe vaporizer.

Reference symbols are used in the Figures to indicate certaincomponents, aspects or features shown therein, with reference symbolscommon to more than one Figure indicating like components, aspects orfeatures shown therein.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a top perspective view of one embodiment of a hand-heldvaporizer 100, and FIGS. 2, 3, 4, and 5 are, respectively, views of atop side 106, a left side 202, a distal end 104, and a proximal end 102of the vaporizer.

Vaporizer 100 includes a housing 101 having a mouthpiece 103 with anopening 311 into the vaporizer at proximal end 102, an air inlet 105 atdistal end 104, and a window 107 on top side 106 through which one canview a botanical material placed within the vaporizer, and a push-buttonswitch 109 on a right side 108. Left side 202 includes a power switch201, a power connector 305, indicator lights 307, and a recess 309.

Housing 101 is formed from a rigid material, and may include one or morepieces or layers of metal or plastic. Thus, for example, sides 108, 202,and ends 102, 104 include a case 207 and a removable bottom panel 303,and top side 106 includes an elongated portion 205 and a bezel 203protruding above and surrounding window 107.

Window 107 is preferably a scratch resistant material that istransparent to visible light, and may be, for example and withoutlimitation, a glass, such as a borosilicate glass or a crystal quartz orfused quartz material.

Vaporizer 100 is preferably sized to be hand-held, and may havedimensions of a height, H, of from 20 to 30 mm, such as height H of 25mm, a length, L, of from 110 to 170 mm, such as a length L of 140 mm,and a width, W, of from 40 mm to 60 mm, such as a width of 50 mm.

Indicator lights 307 may include one light, or several different colorlights (such as red, green, and/or blue) to indicate if vaporizer 100 isbeing powered, temperature settings, and/or battery power remaining inthe vaporizer.

In general, a user may open housing 101 utilizing recess 309 and place abotanical material in a bowl (described subsequently) below window 107,grasp case 207, and push push-button switch 109. In certain embodiments,within several seconds of pushing push-button switch 109 a heater(describe subsequently) within vaporizer 100 emits visible light throughwindow 107 and through air inlet 105 to indicate that a propertemperature has been reached and that the user should inhale thoughopening 311 in mouthpiece 103. The action of inhaling causes air to bedrawn in through air inlet 105 where it is first heated in the heaterand then vaporizes the botanical material, the vapors of which areinhaled by the user through the mouthpiece. In one embodiment, powerswitch 201 has two settings: a power off setting and an on powersetting. In another embodiment, power switch 201 may include severalsettings, such as a power off setting, a low power setting and a hightemperature setting for controlling a temperature of vaporizer 100, andpower connector 305 allows for recharging of an internal battery.

FIG. 6 as a top perspective view of vaporizer 100 illustrating that thevaporizer includes an upper portion 210 and a lower portion 220. Upperportion 210 includes elongated portion 205, bezel 203, and window 107.In addition, elongated portion 205 forms surfaces 611, lip 613, recess615, and includes magnets 621 and a window fixture 631. Window fixture631 further includes include flat surfaces 633 and grooves 635, and isheld onto elongated portion 205 with screws 637, as shown in more detailin FIG. 7.

Lower portion 220 includes case 207, bottom panel 303, mouthpiece 103,air inlet 105, push-button switch 109, power switch 201, power connector305, indicator lights 307, and recess 309. As shown in FIG. 7, air inlet105 is formed from a grill 703 that may be separate from case 207, and awire mesh 705 to prevent contaminants from entering vaporizer 100. Inaddition, lower portion 220 includes a surface 601 and a ledge 603.Surface 601 includes openings into the interior of the housing, andspecifically a first opening 607 and a second opening 605 exposing arecessed bowl 640 having an upper surface 604, which is contiguous withsurface 601 and a bottom mesh 717.

Surface 601 is, or includes, a material that is attracted to magnets621. When upper portion 210 is placed on lower portion 220, as in FIG.1, magnets 621 are attracted to a top 601 such that lip 613 contactsledge 603, surfaces 611 contact surface 601, surfaces 601 and 604contact surface 633, and recess 615 and grooves 635 do not contacteither surface 601 or 604, providing a gap that provides for air flowbetween opening 605 and 607.

A more detailed description of one embodiment of upper portion 210 andlower portion 220 are illustratively shown in FIG. 7, which is asectional view 7-7 of FIG. 2, and FIG. 8, which is a sectional view 8-8of FIG. 3.

Upper portion 210 includes window fixture 631, which is attached toelongated portion 205 with screws 637. Window fixture may also includegaskets or O-rings to provide a gas-tight seal for window 107.

Surface 601 of lower portion 220 is held onto case 207 using screws 701.Grill 703 forming air inlet 105 is attached to case 207, and a wire mesh705 is placed against grill 703 and inside vaporizer 100 to preventcontaminants from entering the vaporizer.

Lower portion 220 also includes a heater section 710, controlelectronics 720, and an energy storage section 730. Heater section 710further includes a heater block 711 including a lower core 702 and uppercore 704 that form having a passageway 713 including a heating element715, and bowl 640 having a mesh 717 bottom, bowl sides 719, opening 605,a temperature sensor, as shown and discussed subsequently.

In one embodiment, heating element 715 is a resistive coil, such as anickel-chromium alloy or a FeCrAl alloy, and cores 702 and 704 aretransparent to visible light, and may constructed, for example, fromborosilicate glass, crystal quartz or fused quartz. Thus when power isdissipated within heating element 715, by providing a voltage across theelement, a glow may be visible through window 107 and/or air inlet 105.In other embodiments, heating element 715 is an induction coil orprovides heat through the combustion of a fuel, such as butane.

Control electronics 720 includes a circuit board 723 on which aremounted a programmable processor 725, a power controller 727, and otherdigital and/or analogue circuitry for controlling and powering vaporizer100, such as power switch 201, power connector 305, and indicator lights307. In addition, other switches, buttons, and sensors, such astemperature sensors, may be dispersed throughout vaporizer 100 and maybe wired into control electronics 720. Additionally, a temperaturesensor may be provided to measure the ambient air temperature, and/or todirectly measure the temperature of air flowing through vaporizer 100,such as near the heating element or near bowl 640. Energy storagesection 730 includes a battery frame 733 attached to case 207 andbattery 731. A temperature sensor may also be provided to measure thetemperature of battery 731 to monitor the operation of the battery.

In one embodiment, battery 731 is a 7.4 V, 800 mAh with a discharge rateof 7 C. In another embodiment, power controller 727 is a switch operatedby programmable processor 725 that can provide time averaged voltages toheating element 715, via a pulse width modulated signal, with a voltageof between zero volts and the current voltage of battery 731. Thus, forexample, if programmable processor 725 determines that a voltage of 50%of the current battery voltage should be provided to heating element715, then the processor provides a 50% duty cycle signal to powercontroller 727.

FIG. 9 is an exploded view of heater block 711, which includes a bottomheat transfer mat 910, a lower core 920, a middle heat transfer mat 930,power and control components 940, an upper core 950, and a top heattransfer mat 960. Lower core 920 and upper core 950 may be, for exampleand without limitation, lower core 702 and upper core 704, respectively.

Lower mat 910 includes an opening 911 and a slot 913. Lower core 920includes an opening 921 that is positioned above slot 913, a groove 922,a heating element support 923, a circular recess 924 with a central meshsupport 925, and element ground receptacle 926 and a heating elementpower receptacle 928. Middle heat transfer mat 930 includes an outerportion 931 and an inner portion 935 that supports mesh 717.

Power and control components 940 include heating element 715 attached toa compression fitting 945 connected to a ground wire 947, and to acompression fitting 943 connected to a power lead 949. Upper core 950includes opening 605 and bowl sides 719. Top heat transfer mat 960includes an opening 961

Mats 910, 930, and 950 are preferably formed from a high-temperaturefood-safe silicone rubber. Lower core 920 and upper core 950 arepreferable formed from borosilicate glass or quartz crystal. Mesh 717 ispreferably formed from stainless steel.

As illustrated in FIGS. 7 and 8, temperature sensor 942 is positioned tomeasure a temperature of body 100 within lower portion 220. Temperaturessensor 942 is preferably a digital temperature sensor, such as memorymodule temperature sensor model MCP9843T-BE/MC (Microchip TechnologyInc., San Jose, Calif.).

More specifically, temperature sensor 942 is positioned on circuit board723. Temperature sensor 942 thus measures temperature of the circuitboard, and does not directly measure the temperature of air bowl 640,which is used to vaporize botanical materials M. It has been found thatthe power levels required for achieving a required temperature may bedetermined by a calibration, which is then encoded into programmableprocessor 725. The calibration between the temperature of the airprovided to air bowl 640 (T_(M)) and the temperature measured bytemperature sensor 942 (T_(TS)) and/or the voltage (V) provided toheating element 715 may be performed, for example and withoutlimitation, by placing a thermocouple in the air bowl and then providingvarious voltages (that is, powers) to heating element until thetemperature measured by the temperature sensor stabilizes. Thus, forexample and without limitation, the calibration between air bowltemperature the temperature measured by temperature sensor 942, and/orthe voltage provided to heating element 715 may be stored in as alook-up table or formula for in the memory of programmable processor 725and used for controlling the temperature of air provide to botanicalmaterials M from the temperature measured by temperature sensor 942.

FIG. 10 is a perspective view of a partially assembled heater block 711.As shown in FIG. 10, upper core 950 also includes a groove 1001, aheating element support 1003, a heating element power receptacle 1005, aheating element ground receptacle 1003, and a temperature sensorreceptacle 1009. Heating element 715 is placed with grooves 922 and1001, and is supported midway by heating element supports 923 and 1003,compression fitting 945 is sandwiched between receptacles 926 and 1007,and compression fitting 943 sandwiched between receptacles 928 and 1005.When assembled, passageway 713 is formed by mated grooves 922 and 1001.

The operation of vaporizer 100 will now be discussed with reference toFIG. 11, which is the view of FIG. 6 illustrating air flow through thevaporizer, FIG. 12, which is a cut-away perspective sectional view ofthe embodiment of FIG. 1, and FIG. 13, which is a schematic view of oneembodiment of the electronics within the vaporizer.

FIGS. 11 and 12 illustrate the placement of botanical materials M withinbowl 640, and the flow of air and vapors through vaporizer 100.Specifically, FIG. 11 shows upper portion 210 removed from lower portion220. This configuration provides access to bowl 640 for cleaning andplacing fresh a fresh botanical material M and to clean otherwiseinternal surfaces 601 and 611, recess 615 and window fixture 631.

When upper portion 210 and lower portion 220 are assembled, as in FIG.1, recesses 615 and 635 form an air passage between bowl 640 and opening607. Specifically, FIG. 11 illustrates portions of surfaces 601 and 604which contact surfaces 611 and 633 (shown as 601 a), restriction orprohibiting air flow, while other portions of surfaces 601 and 604 donot contact recesses 615 or 635 (shown as surface 601 b) and thusprovide an air flow passageway. Thus, as illustrated with arrows, airflow is shown an entering air inlet 105, moving up through bowl 640 andopening 605, between upper portion 210 and lower portion 220 alongsurfaces 601 b, down through opening 607, and then through opening 501.

FIG. 12 illustrates the flow of air from air inlet 105 though bowl 640.Air is drawn though opening 911, along slot 913, up through opening 921,through passageway 713, where the air is heated by contact with heatingelement 715, up through mesh 717 into bowl 640, along surface 601 toopening 607 and through opening 311 of mouthpiece 103.

Temperature Control

FIG. 13 is a schematic 1300 illustrating control electronics 720 ofvaporizer 100. Thus, for example and without limitation, schematic 1300shows connections between power switch 201, push-button switch 109,indicator lights 307, battery 731, programmable processor 725, powercontroller 727, temperature sensor 942, and heating element 715.

In addition to providing temperature control for the process ofvaporizing a botanical material, control electronics 720 may alsoprevents the vaporizer body and internal components from overheating andcausing damage to the battery, computer, or other internal components.

Processor 725 is powered from battery 731 and is programmed with acontrol algorithm to accept input from power switch 201, push-buttonswitch 109, temperature sensor 942, and to optionally monitor thevoltage of the battery to provide power to one or more indicator lights307, and a signal to power controller 727. Power controller 727 in turnaccepts command signals from processor 725 to provide the voltage frombattery 731 to heating element 715. In certain embodiments, theprocessor 725 and power controller 727 provide a processor determinedaverage voltage to heating element 715 by providing a pulse widthmodulated signals to power controller 727, which then provides the timeaveraged voltage (and thus heating power) as determined by theprocessor.

Power switch 201 may have 2 or more setting, as interpreted by firmwarein programmable processor 725, where the setting may include, forexample and without limitation, an “off” setting and an “on” setting, oran “off” setting, a “low temperature” setting and a “high temperature”setting. With power switch 201 in the “off” setting, all electronics invaporizer 100 are powered off With power switch 201 in an “on,” “lowtemperature” or “high temperature” setting, processor 725 executesalgorithms to maintain certain temperatures of heating element 715.

Control electronics 720 are operated to rapidly reach and maintain adesired biological material temperature in vaporizer 100. Althoughtemperature sensor 942 is not located to directly measure thetemperature of the biological material, control electronics 720 may beoperated to achieve a desired approximate temperature. As discussedabove, a look-up table may be provided to processor 725 in the form oftemperature of the air provided to air bowl 640 (T_(M)) versus thebattery voltage (V) provided to heating element 715.

In one embodiment, control electronics 720 may rapidly and accuratelyheat the biological material in vaporizer 100 to a desired temperatureusing an algorithm that provides a voltage to the heating element as afunction of the temporal output of power controller 727 and thetemperature of vaporizer 100 as measured by sensor 942.

Indicator lights 307 may include lights that are programmed to providean indication of the operation of vaporizer 100. Thus, for example andwithout limitation, indicator lights 307 may include a dim green lightthat is powered to indicate that vaporizer 100 is powered on in a lowtemperature setting, a bright green light that is powered to indicatethat the vaporizer is powered in a high temperature setting, blinkingblue light to indicate that the vaporizer is charging, a red light toindicate that battery power is low, and a solid red light to indicatethe device is overheated and has been automatically shut down.

In addition, with power switch 201 in an “on,” “low temperature” or“high temperature” setting, and with push-button switch 109 pressed,processor 725 provides signals to power controller 727 to provideelectric power from battery 731 to heating element 715.

In certain embodiments, control electronics 720 help to preventoverheating due to push-button switch 109 being pressed for anexcessively long time. Thus, for example, programmable processor 725 mayinclude a timer that starts when push-button switch 109 is pushed andwhen that timer reaches some predetermined value, the voltage to heatingelement 715 is reduced in value, which may be as providing no voltage tothe heating element.

In certain embodiments, power controller 727 provides power to heatingelement 715 according to the calibration discussed above. Thus, forexample, in one embodiment, a look-up table relating a desired tomeasured temperature is provided to processor 725 in the form of T_(M)(the temperature of the air provided to air bowl 640) versus T_(TS) (thetemperature measured by temperature sensor 942). For a given desiredvalue of T_(M), the look-up table provides a target temperature T_(TS).Using the target temperature T_(SS) and the measured temperature oftemperature sensor 942, processor 725 may then provide control signalsto power controller 727 with duty cycles that approach and then maintainthe target temperature T_(TS), and thus the desired value of T_(M).Processor 725 may use, for example and without limitation, a look-uptable or a mathematical function based on measured temperature, or acontrol algorithm such as a PID control algorithm, to power heatingelement 715.

It certain embodiments, voltage of battery 731 drops as the batterydischarges. It has been found that in cases where there is a significantchange in battery voltage over time, it is advantageous to adjust apulse width modulated (PWM) signal provided to power controller 727 sothat the voltage, and thus power, dissipated in heating element 715 canbe accurately controlled. In certain embodiments, therefore,programmable processor 725 also measures the voltage of the batteryduring use, so that a known voltage may be provided to the heatingelement.

Thus, for example, the look-up table in processor 725 may be in the formof T_(M) versus V. Processor 725 measures the instantaneous batteryvoltage, and then provides a PWM signal to power controller 727 thatensures that the time average voltage provided to heating element 715corresponds to the voltage provided during the calibration, as describedabove.

In certain other embodiments, the time averaged voltage V to heatingelement 715 is varied according to a current temperature determined bytemperature sensor 942 decreases. Thus, for example, the voltage, andthus, power provided to heating element 715 may be any monotonicallydecreasing function of temperature, such as a continuous function, astep-wise function, or any combination thereof.

As another example of the control algorithm of control electronics 720,power controller 727 may provide several discrete power levels toheating element 715, such as 2, 3, 4, 5, 6, or more power levels. In thefollowing example, processor 725 may instruct power controller 727 toprovide heating element 715 with voltages, and thus power, at one offour power levels (referred to herein, without limitation, as ranging amaximum power level of “HIGH,” to “MEDIUM,” “MEDIUM_LOW,” and a lowestpower level of “LOW”). The instructions may change the power level as afunction of the sensed temperature of temperature sensor 942, a temporalmeasure of the provided power, and the voltage of battery 731. Asdiscussed above, the control algorithm may also maintain the power levelas the battery voltage drops by measuring the battery voltage andadjusting the duty cycle of to achieve the desired time average voltageto heating element 715

In addition to storing several power levels for power controller 727,processor 725 also stores several predefined temperature levels whichthe processor may use, in comparison to measured temperature oftemperature sensor 942 to switch between power levels. Thus, forexample, and without limitation, processor 725 may, in conjunction withthe four levels of this example, store three “cut-off” temperature,referred to herein as “CUTOFF_HIGH,” “CUTOFF_MEDIUM,” and“CUTOFF_MEDIUM_LOW.” The algorithm coded into processor 725 may, forexample and without limitation, operate as in the following pseudo code,where “TIMER” measures the time from the beginning of heating (that is,a timer that starts when the user-operable, push-button switch 109 ispressed), and “STARTUP_TIME” is a predetermined time for an initialpower level of HIGH:

if TIMER < STARTUP_TIME power is HIGH else if TEMP < CUTOFF_HIGH poweris HIGH else if TEMP < CUTOFF_MEDIUM power is MEDIUM else if TEMP <CUTOFF_MEDIUM_LOW power is MEDIUM_LOW else power is LOW if TIMER <BOOST_SECONDS power is adjusted one level higher

As a first step, there is startup time of START_UP, which may be severalseconds, during which the power is set to HIGH. As vaporizer 100 isused, the temperature will likely increase as the result of powerprovided to heating element 715. In addition to providing rapid heatingof the biological material, this will also case heating element 715 toglow and permit the user to see that heating has begun. As thetemperature increases the power level is set to progressively lowervalues: when the temperature is less than CUTOFF_HIGH, the power levelis set to HIGH; when the temperature is greater than CUTOFF_HIGH andless than CUTOFF_MEDIUM, the power level is set to MEDIUM, when thetemperature is greater than CUTOFF_MEDIUM and less thanCUTOFF_MEDIUM_LOW, the power level is set to MEDIUM_LOW; and when thetemperature is greater that CUTOFF_MEDIUM_(—) LOW the power level is setto LOW.

The last line of the code provides an optional feature, a “boost timer”that sets the power level one level higher during an initial operationof vaporizer 100, as indicated in the last line of the pseud code above.Specifically, a power level of HIGH is not affected, a power level ofMEDIUM is increased to HIGH, a power level of MEDIUM_LOW is increased toMEDIUM, and a power level of LOW is increased to MEDIUM_LOW.

The boost timer may be used to provide additional heating if thevaporizer has cooled down from a lack of use. The combination of thestartup timer and boost time allows the user to increase the heatinglevel by pressing the button again while inhaling if they want moreheating.

In another embodiment, BOOST_SECONDS is not used (i.e.,BOOST_SECONDS=0).

In various embodiments, the voltages at the various power levels maycorrespond to, for example and without limitation, a HIGH value of from40 W to 60 W, a MEDIUM value of from 30 W to 50 W, a MEDIUM_LOW value offrom 20 W to 40 W, and a LOW value of from 5 W to 15 W. The CUTOFF_HIGHmay be from 70% to 95% of the target temperature, the CUTOFF_MEDIUM maybe from 60% to 90% of the target temperature, and the CUTOFF_MEDIUM_LOWmay be from 50% to 75% of the target temperature.

As discussed below, vaporization temperatures are generally in therange, for example and without limitation, of from 130° C. to 200° C.The amount of power used to heat air that vaporizes the material dependson the construction of vaporizer 100, such as the thermal mass andamount of material being vaporized, and the amount of air being pulledthrough the vaporizer. The amount heat required to vaporize is expectedto be in the range of from 10 Watts to 100 Watts, though higher andlower powers are within the scope of the present invention.

The target temperature of temperature sensor 942 is selected toeffectively drive off volatiles from the botanical material. While notmeant to limit the use of the present invention, the Table I containseffective vaporization temperatures of some botanical material.

TABLE I Vaporization Temperature of Common Botanical Materials NameScientific Name Plant Part Vaporization Temp. LOW TEMPERATURE: 100° C.150° C. Eucalyptus Eucalyptus globulus Leaves 130° C. Clove: SyzygiumAromaticum Dried Flower 123° C. to 150° C. Buds Lavender Lavendulaangustifolia Leaves 100° C. to 130° C. Lemon balm Melissa officinalisLeaves 142° C. Sage: Salvia Officinalis Leaves 125° C. to 150° C. Thyme:Thymus Vulgaris Herb 100° C. to 150° C. Tobacco: Nicotiana Tabacum Leaf125° C. to 150° C. MEDIUM TEMPERATURE: 150° C.-175° C. Hops Humuluslupulus Cone 154° C. Ginkgo: Ginkgo Biloba Leaves, 125° C. to 175° C.Seeds HIGH TEMPERATURE: 175° C.-200° C. Chamomile Matriarca chamomillaFlowers 190° C. Sage Salvia officinalis Leaves 190° C. Thyme Thymusvulgaris Herb 190° C. Aloe Vera: Aloe Vera Gelatinous 175 C. to 200 C.From Leaves 175 C. to 200 C. Garlic: 175 C. to 200 C. Ginger 175 C. to200 C. Ginseng: 175 C. to 200 C. Licorice: 175 C. to 200 C.

In general, the target temperature as measured by temperature sensor 942is in the range of from 145° C. to 205° C., and may be, for example andwithout limitation, be approximately 145° C., 150° C., 155° C., 160° C.,165° C., 170° C., 175° C., 180° C., 185° C., 195° C., 200° C. or 205° C.For multiple temperature settings, such as a “low temperature” and “hightemperatures,” the low temperature setting maybe suitable for vaporizinglow temperature volatiles such as tobacco and have a temperature in therange of from 150° C. to 165° C., with a value, for example of 150° C.,155° C., 160° C., or 165° C. The high temperature setting maybe suitablefor vaporizing higher temperature volatiles, such as ginseng, and have atemperature of 190° C. to 205° C., with a value, for example of 190° C.,195° C., 200° C., or 205° C.

Examples of the Use of the Vaporizer

The following are examples of the user of vaporizer 100. With referenceto FIGS. 1 and 3, with power switch 201 in an “off position,” a usergrasps lower portion 220 in one hand and places their thumb in recess309 to remove upper portion 210. With reference to FIG. 6, a user maythen clean the various internal surfaces and bowl 640, and place a freshsample of a botanical material in the bowl. Upper portion 210 may thenbe securely placed on top of lower portion 220.

As shown in FIGS. 6 and 7, a user may, at any time, look through window107 to verify the presence of a botanical material.

Next, the user switches power switch 201 to an appropriate non “off”setting (such as “on,” “low temperature,” or “high temperature”).

Next, the user presses push-button switch 109. Within a few seconds,control electronics 720 has provided sufficient power to raise the airnear temperature sensor 942 to the target temperature, as stored withinprocessor 725. The glow from heating element 715 may be seen by the userthrough window 107 and/or through air inlet 105. For certain botanicalmaterials the extracted vapor may also be viewed through window 107.

With the visible indication of a proper temperature, the user may theninhale through mouthpiece 103. Air is then drawn into air inlet 105,through passageway 713, through the botanical material in bowl 640,between grooves 635 and surface 601, along surface 601 into opening 607,and then through opening 311 to the user's mouth.

The majority of power provided to heating element 715 heats air withinpassageway 713, and thus the botanical material within bowl 640 isvaporized convectively as the hot air flows through the botanicalmaterial.

The surfaces which contact the heated air as it flows between surface601 and upper portion 210 will act as a “heat sink,” causing the gasesto cool from high temperature of heating element 715 to approximatelyroom temperature. After inhaling, the user then releases push-buttonswitch 109, which reduces the power though heating element 715.

It will be understood that the apparatus described herein includes, butis not limited to, certain digital and analog components. It will beunderstood that the invention is not limited to any particularimplementation, programming technique, or combination of analog ordigital components, and that the invention may be implemented using anyappropriate devices or techniques for implementing the functionalitydescribed herein.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure or characteristicdescribed in connection with the embodiment is included in at least oneembodiment of the present invention. Thus, appearances of the phrases“in one embodiment” or “in an embodiment” in various places throughoutthis specification are not necessarily all referring to the sameembodiment. Furthermore, the particular features, structures orcharacteristics may be combined in any suitable manner, as would beapparent to one of ordinary skill in the art from this disclosure, inone or more embodiments.

Similarly, it should be appreciated that in the above description ofexemplary embodiments of the invention, various features of theinvention are sometimes grouped together in a single embodiment, figure,or description thereof for the purpose of streamlining the disclosureand aiding in the understanding of one or more of the various inventiveaspects. This method of disclosure, however, is not to be interpreted asreflecting an intention that the claimed invention requires morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive aspects lie in less than allfeatures of a single foregoing disclosed embodiment. Thus, the claimsfollowing the Detailed Description are hereby expressly incorporatedinto this Detailed Description, with each claim standing on its own as aseparate embodiment of this invention.

Thus, while there has been described what is believed to be thepreferred embodiments of the invention, those skilled in the art willrecognize that other and further modifications may be made theretowithout departing from the spirit of the invention, and it is intendedto claim all such changes and modifications as fall within the scope ofthe invention.

We claim:
 1. A method of controlling electric power provided to avaporizer, said method comprising: accepting a signal from auser-operable switch; providing electric power to a heater of thevaporizer upon accepting the signal from the user-operable switch;measuring a signal indicative a temperature of the vaporizer; anddecreasing the electric power to the heater if the measured temperatureof the vaporizer increases.
 2. The method of claim 1, wherein theproviding electric power is provided at one of a plurality of discretepower levels.
 3. The method of claim 1, wherein the decreasing decreasesthe electric power as the temperature increases above one of a pluralityof predetermined temperatures.
 4. The method of claim 1, wherein saidaccepting a signal from a user-operable switch actuates a timer, andwherein the electric power is increased during an initial time.
 5. Themethod of claim 1, wherein said user-operable switch signal is a buttonon the vaporizer.
 6. The method of claim 1, where providing electricpower further provides electric power to a lighting element on thevaporizer.
 7. The method of claim 1, wherein the signal indicative atemperature of the vaporizer is a signal provided by a temperaturesensor within said vaporizer.
 8. The method of claim 1, where saidmethod further includes flowing air through the vaporizer, and wheresaid heater includes a heating element configured to the air.
 9. Themethod of claim 8, where said providing electric power to a heaterresistively heats the flowing air.
 10. The method of claim 1, where saidmeasuring a signal indicative a temperature of the vaporizer includesmeasuring a temperature that is not the temperature of the flowing air.11. A vaporizer to provide a user with vapor from a botanical material,said vaporizer comprising: a user-operable switch; a temperature sensoradapted to provide a signal indicative of the temperature of thevaporizer; an electric heater configured to heat the botanical material;and electronics adapted to sense actuation of said user-operable switchand accept said signal indicative of the temperature of the vaporizer,and to provide electric power to said electric heater, where theprovided electric power decreases with an increase in the temperature ofthe vaporizer.
 12. The vaporizer of claim 11, wherein the providedelectric power is one of a plurality of discrete power levels.
 13. Thevaporizer of claim 11, wherein the provided electric power decreases asthe temperature increases above one of a plurality of predeterminedtemperatures.
 14. The vaporizer of claim 11, wherein said electronicsincludes a time actuated by said user-operable switch, and wherein theelectric power is increased during an initial time.
 15. The vaporizer ofclaim 11, wherein said user-operable switch is a button on thevaporizer.
 16. The vaporizer of claim 11, wherein said electronics isfurther configured to light a lighting element on the vaporizer.
 17. Thevaporizer of claim 11, where said vaporizer includes a passageway forthe flow of air into the vaporizer, over the electric heater, and oversaid botanical material.
 18. The vaporizer of claim 11, where saidelectric heater resistively heats the flow of air.
 19. A method ofcontrolling electric power provided to a vaporizer, said methodcomprising: measuring the voltage of a battery providing power to theheater; and providing the battery voltage to a heater of the vaporizeraccording to a duty cycle, where said duty cycle is inverselyproportional to the measured voltage of the battery.
 20. A vaporizer toprovide a user with vapor from a botanical material, said vaporizercomprising: a battery having a voltage; an electric heater that acceptsthe voltage and generates thermal energy to heat the botanical material;and electronics to switch the accepted voltage on and off according to aduty cycle, where the duty cycle is inversely proportional to a measuredvoltage of the battery.
 21. The vaporizer of claim 20, where saidvaporizer includes a passageway for the flow of air into the vaporizer,over the electric heater, and over said botanical material.
 22. Thevaporizer of claim 20, where said electric heater resistively heats theflow of air.